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A102817
Decimal expansion of Gamma(delta)^2 where delta is the Feigenbaum bifurcation velocity constant (A006890).
1
2, 1, 7, 9, 9, 9, 9, 7, 6, 4, 4, 9, 9, 9, 8, 8, 1, 4, 6, 8, 6, 2, 8, 8, 1, 3, 9, 5, 7, 7, 9, 3, 6, 0, 9, 8, 9, 0, 7, 2, 6, 7, 9, 7, 8, 9, 0, 9, 7, 3, 0, 0, 5, 6, 5, 4, 8, 3, 2, 8, 8, 5, 2, 1, 2, 2, 4, 0, 4, 2, 3, 7, 7, 2, 0, 9, 6, 4, 2, 6, 1, 4, 9, 8, 3, 9, 2, 3, 1, 1, 2, 6, 8, 1, 5, 0, 7, 1, 6, 5, 3, 3, 0, 8, 6
OFFSET
3,1
COMMENTS
Let x be this constant, then Integral_{t=1..x} sin(t)/sqrt(t) dt = 0.655555692248871113068...
delta^2 = 21.8014436664499573..., (delta/Gamma(delta))^2 = 0.10000663312663433933000349...
If s is solution of Gamma(s) - sqrt(218) = 0 then 1/((s - delta)*Gamma(delta)^6) = 2.5555951358396... whereas a^(Pi/4) = 2.055596478435... where a is Feigenbaum alpha constant (A006891), the difference = 0.4999986574... ~ 1/(2 + 10^-5.27)
10*cos(Gamma(delta)^2) + Pi = -0.199999019922688714710053...
EXAMPLE
217.99997644999881468628813957793609890726797890973...
MATHEMATICA
Set delta then RealDigits[Gamma[delta]^2, 10, 110][[1]]
PROG
(PARI) acos(Pi/10+.0199999019922688714710053)+69*Pi \\ Yields ~ 30 digits. Using (2e5-1)/(1e7-1) yields ~ 15 digits. For a better value use, e.g., delta from the Broadhurst link. - M. F. Hasler, Apr 30 2018
CROSSREFS
Sequence in context: A141513 A258058 A238223 * A026252 A032298 A032210
KEYWORD
cons,nonn
AUTHOR
Gerald McGarvey, Feb 26 2005
STATUS
approved